Not able to perform filtering or Terrain Correction after SAR Calibration

I use the following code to run the CALIBRATION (sigma0) over the radarsat2 SLC. The result looks good, but I am not able to use it as the input for either filtering or Terrain Correction. It sounds like that the info. for Tie Point Grids (e.g., “Slant range time” and “Incidence Angle”) is missing!

I would be grateful if sb. could explain me what does go wrong?

c:\Program Files\snap\bin\gpt.exe" Calibration -Ssource=‘2014111_HH_SLC\product.xml’ -PsourceBands=‘Intensity_HH’ -t ‘myband1.tiff’ -f ‘GeoTIFF’ -PauxFile=‘Product Auxiliary File’ -PoutputDNBand=‘true’

Hi SAR2016,

I’m not very familiar with the GeoTIFF format, but I tested exporting a product to this format from the GUI and reproduced your issue. Indeed, Slant range time and Incidence Angle aren’t exported along with the latitude and longitude tie-point grids. Perhaps someone who knows this format better can help you change this (if it can be changed).

Is there a particular reason you work with GeoTIFF ? May I suggest using the BEAM-DIMAP format instead? All my RS2 SLC processing is done with this format and it’s going very smoothly so far. The slant range time and incidence angle would be included in your calibrated product and you would be able to run your terrain correction.



As SDufourBeausejour suggests it would be best to stay in BEAM-DIMAP format till the end of the processing and export only at the end to the format you need.
When storing tie-point grids to GeoTIFF they get converted into normal bands. And this is probably the reason why terrain correction is not working. It looks to specific for tie-point grids where it should look more generally for raster data nodes.
This is at least what I noticed by quickly looking at the code.

1 Like

Sorry, I just noticed your messages. Thanks for your advice. You’re right. I have tried it through BEAM-DIMP and saved the final ortho in geotiff.

Thanks again